The forensic industry continues to evolve as science and technology advances. With these advancements comes a higher demand for specialized staff. Crime Scene Investigators, commonly referred to as CSIs, are forensic evidence technicians who are specifically trained in the detection, collection, processing, and preservation of forensic evidence recovered in connection with and/or at crimescenes. CSI Units are the “front line” in the forensic industry.

A CSI Unit is responsible for, but not limited to, the following tasks:

  • Detection, preservation, processing, and collection of physical and scientific evidence recovered at crime scenes
  • Expert courtroom testimony
  • Latent print examination
  • Detailed crime scene drawings for courtroom presentations
  • Vehicle examination

To accomplish these responsibilities, the CSI Unit needs certain spaces within a forensic facility. They must be armed with an impressive array of technology and equipment to effectively do their job. Most law enforcement agencies do not have an adequate facility and are in desperate need of new equipment to support a CSI Unit.

What are the facility requirements to support a 15 to 20 person CSI Unit? The NIJ Blue Book has a wide range of suggestions to answer this question, but what does it really take for a CSI Unit to efficiently complete day to day activities? Experience teaches that the design and construction of forensic facilities that support a CSI Unit have the spaces and components outlined on the next pages.

The triage area is a large, open area designed to house the initial reception of evidence. This is where each piece of evidence is received, then moved to the appropriate place for further examination, packaging, and distribution. This space is fit out with a perimeter fixed bench and has sinks, ventilated enclosures, and floor equipment. Forensic exam tables (FXT) are placed in the center of the triage area with service wings above equipped with power, data, exam light, and snorkel. A typical triage area is made up of 12 planning modules.

Triage Area

Fixed perimeter bench is usually identified as casework. The countertop depth is 30", however the base cabinet itself is 22" deep (a standard dimension). Eight inches is left open for a service chase which occupies the distance between the wall and the back of the cabinet. This space allows the services to be distributed without interfering with the wall cavity.

A forensic exam table (FXT) is movable casework designed to accommodate the various needs of an examiner. Options of a FXT include, but are not limited to: locking casters, leveling feet, adjustable height (manual or electric), bottom shelf or foot rail, under carriage support for an alternate light source or a computer’s CPU, locking cabinet, and a keyboard tray. The countertop of a FXT can be a variety of materials including wood, a chemical resistant material, or stainless steel. Another benefit of a FXT is the fixed or removable upright support for shelving, microscopes, monitors, cameras, and/or clip bar.

A service wing is a floating service chase. It is suspended from the structure above and floats below the ceiling allowing easy access to electric, communication, gas services, exhaust, and task lights. This frees up floor space and allows for a greater degree of flexibility.

A planning module is a building block for a state-of-the-art forensic facility. It creates a net area of space that is equal in “X” and “Y” dimensions. For the purpose of this article, One planning module is 11 feet by 11 feet, which creates 121nsf. For example, a generic planning module would allow for perimeter bench on two walls separated by an aisle of non fixed bench and a FXT in the center of the space. The actually dimensions of a planning module may change for each facility due to structure, infrastructure, or function but the design intent of the space would not. Modular planning leads to a flexible and efficient design solution, which extends the life of the facility.

The next space is an evidence drying room. This space should be adjacent to the triage area to minimize the movement of evidence. A typical evidence drying room is made up of two planning modules. This space has a sink, re-wrapbench, and evidence tracking system (ETS). The room is equipped with several evidence drying cabinets (EDC). The number of EDCs is dependent upon the case load of each agency. EDCs add a greater level of flexibility to thespace.

An evidence drying cabinet (EDC) is a pre-engineered solution that looks like a tall, free standing cabinet. It is typically constructed of a single, polypropylene interior shell. It can be thoroughly washed out, with the water emptying into an external floor drain. The door is normally see-through, with an air filter in the lower half of the door. There is a second air filter located at the top of the cabinet. These are a combination of charcoal and HEPA filters that clean and re-circulate the air back into the room.

There are two outlooks on an evidence tracking system (ETS). The first insists evidence tracking should not begin until the evidence is received at the laboratory. The second outlook believes evidence tracking should begin as soon as the evidence is collected. Each facility’s operational practice will influence the final decision of which ETS method to use. A typical ETS setup will include a computer, bar code scanner, and a bar code printer.

The field equipment room is very important to the CSI Unit. This space is best suited between the triage room and the service yard. A standard field equipment room is made up of two planning modules. It is designed to provide the CSI Unit with storage space for their field equipment and space to replenish their supplies before leaving the facility for the next assignment. The room is fitted with perimeter fixed personnel lockers on one side and standing bench with supplies on the opposite side.

Exam Room

A 1 1/2 planning module exam room would allow up to four investigators to move freely around a set of FXTs. The furniture and equipment in this space includes a sink, two FXTs, a supply storage cabinet, and a service wing above with power, data, exam light, pole scope, and snorkel. This space could also serve as a temporary evidence storage room. It is possible to utilize a standard operating procedure to secure this space for a period of time to manage acase. However a secure, dedicated room with wire shelving, individual lockers, and refrigerator would be a greater benefit to the CSI Unit and only requiresone planning module.

Latent Print Lab

Some CSI Units are also responsible for processing latent prints collected at the crime scene. To accomplish this, a latent print processing lab is needed. This lab can function as one large space or can be sub-divided into smaller rooms by task. The functions and planning modules include: super glue, three modules; ninhydrin, two modules; D.F.O., two modules; and dusting, three modules. These tasks require special ventilation, casework, a sink, plus specific equipment.

Super glue requires fuming chambers that are ventilated to remove the fumes after the super glue is heated and vaporized. Ninhydrin needs a chemical fume hood to properly utilize liquid chemicals. D.F.O. also requires a chemical fume hood. This fume hood needs a large sink up front. Dusting entails proper ventilation for dusting chambers. These chambers should vary in size to allow both large and small items for examination. At least two image capture rooms are also needed to support these four functions.

Vehicle exam bays (VEB) are needed to support a CSI Unit. VEBs should be adjacent to the triage area. Twelve planning modules are needed for one bay. Most facilities require three to four bays with one bay containing a portable vehicle lift. This provides the ability to examine the under carriage of a vehicle. If the VEBs are configured properly with the correct standard operating procedures, the bays can be linked side-by-side. This configuration can then accommodate a semitrailer entering from the side of the facility.

This space would typically include a sink, re-wrap bench, storage space, evidence tracking system, and a chemical fume hood. Each VEB should be equipped with an overhead rolling door, compressed air to drive pneumatic tools, a tool chest, and cleaning tools (broom, mop, squeegee, and shop vacuum). The floor drains need a sediment trap as well as an oil and water separator. Height is an important consideration for a VEB. If you include the height needed to stand under a vehicle, the height of a vehicle, services above, and structure, a VEB must be 1 1/2 to 2 stories.

Separate shower and locker rooms for male and female staff are important within a forensic facility. The shower and locker rooms should be located betweenthe triage space and the exterior. This will give the staff direct access to clean up before and after they work in the triage area. These rooms will typically equal four planning modules. Non-technical, public space is alsoneeded, for example: personal offices, conference rooms, and break rooms.

Each agencies facility needs will differ but the value of the CSI Unit does not change. They are a key element to each successful criminal prosecution. Thisis why forensic facilities must support the “front line” with thespaces identified above.

Ken Mohr is a Principal and Sr. Forensic Laboratory Planner with Crime Lab Design, which provides full A/E services for forensic and medical examiner facilities.